Suspension Suggestions

New to the site and all but wondering if you could recommened an efficient suspension setup for my situation. My truck is constantly being used for heavy loads and its a base model 1500. I own a 24' Sea Ray which wieghs minimum 4800lbs.

The back sags quite a bit and seems to be alittle more bouncey then i'd like. What kind of shock/strut package would I need?

You could also go the real cheap but effective route- put a set of helper springs on the leaf spring pack.I like them because they do not really affect the ride of your truck until you put enough weight on the rear of the truck to load up the helper springs. Like I said, old school and kinda primitive- but under a hundred dollars and quite effective.

Bilsteins would work well. One thing I usually recommend is firestone air springs. I have installed them in a few trucks and they work really well. I looked them up for the suburban and it is an airbag inside the spring(coilrite) so a little different than the truck ones (riderite). their a lot cheaper than the truck air springs which is always nice. The suburban ones are just rated lower than the truck ones. heres the manufacturers site www.firestoneindustrial.com and you can get them from summit racing for cheap http://www.summitracing.com/parts/FIP-4108/ The nice thing about the airsprings is you can manually inflate when you need to get rid of the sag or you can buy the automatic leveling system so you set the height and it will adjust automatically to loads.